(1) Field of the Invention
The present invention relates generally to drywall construction, and more particularly to an improved metal corner bead with paper legs.
(2) Background Information
Current building construction utilizes sheets of drywall, commonly referred to as “wallboard,” to form the surfaces of interior walls of buildings. Drywall is typically formed of sheets of plaster sheathed in an outer wrapping of heavy construction paper.
In drywall construction, joints between adjacent sheets of drywall are usually covered by a paper tape extending lengthwise along the joint. To finish exterior corners in wallboard construction, metal corner beads and bullnose beads are typically installed. Similarly, metal trim is used to protect and finish a wallboard edge at window and door jams, while expansion joints are inserted between sheets of wallboard at predetermined intervals within buildings.
The above-described corner bead and trim products include metal flanges projecting outwardly, which are perforated with circular holes or elongated slots, so that the trim product may be fastened to the drywall panels using nails or the like. Wet plaster is then smoothed into place to cover the metal flanges, and edges of the plaster are smoothed and feathered to cover and conceal the metal edges.
Another type of corner bead is referred to as a “tape-on” bead. Tape-on corner beads utilize a strip of paper covering the exterior surface of the metal corner angle, with wings projecting outwardly from the legs of the corner angle. Wet plaster or joint cement secures these paper wings to the drywall, to secure the corner bead in position, rather than using nails or other fasteners. However, one problem associated with such “paper bead” is the scuffing and damage to the paper covering the curved nose of the bead once the bead has been installed on a corner. Because the curved nose portion of the bead is directly exposed, and has no plaster or other material covering the paper, the paper may be easily scuffed or torn with only minimal contact.
One known attempt to overcome the problems associated with conventional tape-on corner bead is disclosed in U.S. Pat. No. 6,073,406 to Raymond Kearney. This patent discloses a corner bead assembly with offset flanges that are sandwiched between front and rear layers of flexible material. These layers are adhered to each other past the terminal edge of each of the offset flanges and are adhered to each of the offset flanges as well.
While this assembly apparently works sufficiently for its intended purpose, it also suffers drawbacks. The cost to manufacture the product is greater than necessary because of the use of two layers of flexible material, such as paper. Second, this cost is increased by virtue of the fact that the front and rear layers must be accurately positioned in order to provide the desired overlap, so that the layers can be adhered to each other (in yet an additional manufacturing step) in the area where they protrude beyond the terminal edges of the flanges. Thus, cost of material is high, and time required for manufacturing is high.
The corner bead of the present invention overcomes these drawbacks by the application of paper only to the forward faces of the legs of the metal angle.